This section temporarily contains information copied directly from Bulbapedia, and needs to be rewritten so not to be classified as plagiarism.

“The environment of the Alola region, where strong sunlight pours down all year round, brought about this change in Exeggutor’s form. The people of Alola boast that the Alolan Exeggutor is the true form of Exeggutor. Unlike other Exeggutor, the Alolan Exeggutor has a fourth head—on its tail! This fourth head controls the tail independently and can take on opponents to the rear that can’t be reached by the main heads’ attacks. This Pokémon excels at whipping its long neck like a lash to attack with its hard heads. But that neck can sometimes become a weakness...”

Because of the abundance of sunlight in the Alola region, Alolan Exeggutor grow to be over five times as tall as its counterpart, with its neck stretching up, resembling a palm tree. In addition, it grows a fourth, different head on its tail that can act independently and defend its rear. Alolan Exeggutor uses its long neck like a lash to attack enemies with its hard heads. But its long neck can also be its weak point if not defended properly.